APOE and Alzheimer disease: To assess whether sex, age, or ApoE4 modulates the Aβ to p-tau axis, we included 144 CN Aβ− controls, as well as 178 participants across the AD spectrum as defined by Aβ+ status [CN/MCI/Demented=48/115/15] with cross-sectional and longitudinal CSF p-tau181 data.